1. Field of the Invention
The present invention generally relates to septic systems and, more particularly, to a septic tank having an internal support system and a mold for manufacturing the same.
2. Background Description
Septic systems are widely used for a variety of applications ranging from single family homes to industrial applications. These systems also vary greatly in design; namely, aerobic and anaerobic type systems. In either type of septic systems, the main objective is to treat wastewater in the most efficient manner in order to ensure that the water is properly filtered for distribution within a drain field or other distribution system.
In septic systems, a septic tank and other components are buried in the ground at a certain predetermined depth depending on many variables such as, for example, water tables, types of soil conditions, types of septic systems and the like. By way of example, in areas of high water tables, the septic tank may be buried at low depths leaving approximately six to eight inches of soil above the septic tank; whereas in other areas the septic tank may be buried at higher depths leaving approximately three or more feet of soil above the septic tank. Of course, the septic tank may also be buried at other depths depending on local ordinances and regulations or other engineering considerations.
Septic tanks may also include several components ranging from manholes for gaining access thereto as well as inlet and outlet pipes. Also, in most applications, the septic tanks are constructed from concrete or synthetic materials. In the case of using synthetic materials, a structural ribbed configuration is used to provide strength and durability to the septic tank, itself. The structural ribbed configuration may vary in spacing as well as wall thickness, depending on the specific application of the septic system. However, the use of small spacings between the structural ribs as well as the use of thicker walls leads to higher manufacturing costs due to more material being used to manufacture the septic tanks.
Once the septic systems and more particularly the septic tanks are properly buried in the ground, several external forces or loads are placed on the side walls and top portion of the septic tank. For example, in low water table areas, water will surround the septic tank resulting in high lateral stresses being placed on the side walls of the septic tank. In other areas, such as those with low freeze lines, the septic tank must be buried deep into the ground with upwards of three (3) feet or more of soil placed on a top portion of the septic tank. This amount of soil may cause both lateral and vertical stresses on the septic tank. In both of these situations, the septic tank may be designed with one or both thick walls and closely spaced structural ribs. Again, this leads to high manufacturing costs.
In either of the above situations, the use of both thick walls or closely spaced apart structural ribs still do not adequately protect the septic tank from damage. That is, the lateral or vertical loads imposed on the septic tank may cause cracking of the tank which results in leakage of wastewater. Also, these same loads may deform the manholes which result in inadequate sealing of the manhole cover over the manhole. In extreme cases, a catastrophic failure of the septic system may result; that is, the septic tank may collapse under the weight of the soil or other loads placed thereon. It is also known that the septic tank may begin to bow or sag causing the formation of sink holes in the overlying ground. The sink holes are both dangerous and aesthetically unpleasing.
The present invention is adapted to solving these and other problems.
An object of the present invention is to provide a septic tank which can withstand either or both lateral and vertical stresses caused by loads being placed on the walls of the septic tank.
Another object of the present invention is to prevent cracking of the septic tank.
A further object of the present invention is to prevent wastewater from leaking from the septic tank.
A still further object of the present invention is to prevent deformation of a manhole of the septic tank in order to provide a proper seal between the manhole and a manhole cover.
Still another object of the present invention is to provide a septic tank with low manufacturing costs.
A still further object of the present invention is to provide a septic tank which will not collapse or deform under external loads.
In one aspect of the present invention, a septic system having a septic tank with a sidewall, a top portion and a bottom portion is provided. The septic system also has at least one support structure disposed within the septic tank for providing structural support to the septic tank.
In another aspect of the present invention, at least one support is integrally molded to an interior portion of the septic tank. The septic tank includes opposing sidewalls, a top portion and a bottom portion.
A mold is also provided for molding the septic tank. The mold may be either separable mold portions or an integral mold forming the top, bottom and sidewalls of the septic tank. In the separable mold portions, extensions are provided and in the integral mold pins are provided to form the supports.